Punch-press guard



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EDGAR PUNCH PRESS GUARD Filed Nov. so. s Shengsmet 1 attoz w14 i F. M. EDGAR PUNCH PRESS GUARD I Filed Nov. so. 1923 s sheer-sheet 2' gn vente@ 'j www? if F. M. EDGAR PUNCH PRESS GUARD Filed NOV 30. 1923 5 Sheets-Sheet 5 Patented July 22, 1924.

usarse STATES PATENT caries.

FRANK M. EDGAR, OF DETROITpMIC-IIGN, ASSIGNOR TO TERNSTEDT MANUFACTUR- ING COMPANY, OF DETROIT, MICHIGAN, A CORPORATION 0F llviICIIIGAN.

PUNCH-PRESS GUARD.

Application filed November 30, 1923. Serial No. 677,650.

To au whom it may concern:

Be it known that I, FRANK M. EDGAR, a citizen of the United States, residin at Detroit, in the county of VVayneand tate of Michigan, have invented certain new and useful Improvements in Punch-Press Guards, of which the following is a specification. l

This invention relates to punch press guards. It is not broadly new to provide a punch press with a guard so coupled up with the clutch release that the clutch or trip cannot be disengaged until the hand guard is completely down. Numerous patents in the prior art show devices for this purpose. Noris it broadly new to couple up with the punch press guards a positive stop which is not removed from the path of the clutch release until the guard is way down.

My improvement belongs to punch press guards of the latter type, but has an improved arrangement of structure to make the operation of the parts more reliable and easier, and the counterbalancing device is coupled up directly to the clutch release stop so that the stop will be reliably returned into the path of the clutch release or tripping device when the guard is drawn upwardly. So Yfar as I aml aware all punch press guards which are coupled up with the clutch release are calculated to severely pinch the hand if the operators hand is caught under the guard. I have an arrangement whereby a` yieldable connection is afforded in the dra-ft Aline between the pedal and the guard, whereby-the hand receives only the impact of the guard and any foot pressure is absorbed in the spring so that pressure of the foot as long as continued on the pedal does not serve'to painfully pinch the hand.V Y

In the drawings:

Fig. l is an elevational view of a punch press showing the guard assembled thereon.

Fig. 2Yis a section on the line 2 2 of Fig. 1.

Fig. 3 is a section on the line Fig. 2.

Fig. l is a detail in perspective of the grooved block.

Fig. 5 is a section on the line 5-5 of Fig. l showing the adjustments for correctly positioning the' guard with respect to the dies.

`block by means of the said stud j?.

. Fig. 6 is a section on the line 6 6 of Fig. l showing the yieldable connection between the guard and the draft member.

Fig. l.

Fig. 8 is a detail in perspective of one corner of the guard plate.

A punch press a rotatably supports 4a shaft b to which is secured the pulley a and the shouldered trip collar l which isV Secured on the side of the machine andv spaced therefrom is afplate 7L, which is provided with a slot z' in which a grooved block j is slidably engaged. rIhis grooved block is tapped as at 7c andthe rod`V m is screwed into the stud VTb which is in turn screwed into the tapped hole k to positively connect the grooved block with the stopryo. Thestop 0 is adapted to engage the trip collar CZ to prevent the machine from being operated to force the dies e and j together. (See Fig. 2.)v A pin p isV carried by the grooved slide and a draft bar g provided withv an 'elongated slot 1" is securedto the The extreme lower end of the bar Q is secured to a rod s which is in turn secured to the foot pedal t. Obviously as the foot pedal is depressed it will kpull thebar g down wardly tending to disengage the stop 0 and shouldered trip collar CZ.V

However, additional mechanism is provided whichwill prevent the Vstop frombecoming disengaged from .the shouldered trip collar` until the operator withdraws his hands from between the dies.y vrIhe guard arm uis pivcted to the machine as at e Tis a section on the line (1-7 ofA (see also Figs. 6' and 7) and adjustably` supports on the free end thereof a bracket w which inV turn adjustably supports thev guard plate At an intermediate portion of the said guard arm is secured a Vfixture Q/ which is cut away asat a (Figv 7) to provide an opening through which the draftbar Q may be slidably supported. The

bar g and a pin 4l connects the bracket 8 and pin l. A coiled compressionespring is interposed between the bracket@ and the pin l and normally forces. the pin down-- wardly'tosthe full extentofthe. slot 2.. rlhis springis of sucha strength .thatras the foot lever is depressed carrying with it the draft member g, it will not be compressed] to any appreciable extent but will force the guard arm u downwardly and as the foot pedal is depressed to the full extent of its movement, the guard arm plate x wllassume a position as shownin the full lines of Fig. l. The dotted line position of the guard'in Fig.v l shows the inoperative position of the same, i. e., when the foot pedal is raised and the stop 0 is in engagement with the shouldered'tripv collar (Z.

Pivotedto the plate h as at 6 is a. segmental stop 7 which is provided with' an arm extending to the rear ofthe machine to which is secured a counterweight 8. In Figs. l-'to 4l inclusive, one will notice that the segmental stop 7 when in an interfering position is positioned directly below the grooved block thereby preventing the same from being pulled downwardly when the draft member is pulleddown. As the draft member is pulled A'down the pin p will travel in the slot rand yallow a relative movementbetween the draft member andthe block j carried by the tripping mechanism. The segmental stop,v however, is also provided with an rarm 9 the freek end'of which is connected to theguard arm u bymeans of a link 10. As theI footvr leverl isv depressed the guard arm will be drawn downwardly froml the dotted liney and position to the full line position through theconnecting link 10 and actuatef the segmental stopHT so as' to rot-ate the samein-a counter-clockwise direct-ion 'th-us moving `the cam from-an'nterfering position to a non-interfering-fposition with' respectv to the ofroovedlblock The guard plate is so adjusted that: when theplate reaches a. position shown in full'` lines inv Fig: l the-segmental'stopwill justrelease the block y', to allow the same to be pulled downwardly by 'the draft member through thef-p-in and-slot connection.- Th'isfwill d-isengage the stop o 4from the shoulder trip-d` and allow the operating mechanism to reciprocate the plunger'so'as to bring the dies together.v Another function of the spring 'is to allow the draft-member Q' to be pulled downwardly after the guard is stopped. "Vhenthe guard reaches the full line position, the segmental stop 7 releases the grooved block andthe spring 5 is compressed o-n further movement of the foot pedal to allow for the relative movem'entj between the draft member and the` guard inv tripping the' machine.

The grooved block j is cut away as at 11 to allow only a limited movement of the block in releasing the stop 0 rlhe shoulderL 12:' isl adapted tow strike the segmental stopk to stop further downward movement of the block and hence prevents any further movement of the stop. 0 than is necessary to release the collar. d.

Wvhat I claim is:

l. In-ag-uard for av punch press or similar machine, the combination of operating mechanism,.means for controlling the operating mechanism. and provided with a tripping mechanism :having'a slidable member7 adraft' memb'er having` a lost motion connectionvwith` the tripping mechanism, a stop in the form of asectorwhich is swung in the path-of saidslidablev member which is part ofsaid tripping mechanism-for preventingtlre same from being actuated, and a guard yield-ably connected to saidfdraft member and" positivelyy connected to the stop, whereby the: operating mechanism is lreld inan inoperative positionv unrtil the gu-ardis lowered-to a position in front of they work thereby retracting the stopfto allow the draft member to actuate the tripping mechanism and preventing the operator fronrinserting his hands while the machine isvin operation 2. In a-gnard for punch press or similar mach/ine, `the combination of mechanism for operating-f the 'mach-ine, meansy for tripping the operating mechanisma av draft member sli'dablysup-ported on the machine-and connected-with said'tripping means, a guard p-ivotally` supported-on the-machine, a stop arranged to'be engageablle' withsaidftripping mea-ns,- a bracket carried by the draft member, sa-icldraft member lprovided with a: slot, a pincarried bythe guard projecting thfrouglfsaid slotj andla spring interposed' bfetweenrsarid'bracket andpinto provide a yieldable connection between the draft memb'er and gu-archy the said slot limiting the relative 4movement betweenI th'er two.

3. Ina guiardfor punch press orsimilar m-axehine, tlre-combination-0f mechanism for operatinglth'e machine, means for tripping the operating mechanism andincluding a block slidably supported' on the machine, saidE block provided with a pin, af draftmemberprovided? with an elongated slot which engages with the pin for the purpose of providing a lost motion connection betv'een-tlredraft mem-ber andthe block, a stop normally engaged under they block to preventthev trippingmea-ns from releasing the operating mechanism', and a guard connccted with said stop and,v yieldably connected with the draft member, whereby as th'e--di'aft memberis pulled downwardly the guard is lowered to a protectin'gposition in frontof `the worlr thereby actuating the stop to remove the same from beneath the block to allow the tripping of the operating mech'- anism for the purpose of setting the ma.-

MID

chine in operation when the guard is lowered.

4. In a guard for a punch press or similar machine, the combination of an operating mechanism, means for tripping the operating mechanism, a draft member having a lost motion connection with the tripping means, a stop normally engaged with the tripping means to render it inoperative and provided with a forwardly extending arm and a rearwardly extending arm having a ooun terbalancing member secured thereto for normally holding the stop in such position, a guard pivoted to the machine and connected to said draft member, and a link ture.

FRANK M. EDGAR. 

